1. Technical Field
The present invention relates to a solder ball supplying apparatus, and more particularly, to a solder ball supplying apparatus for supplying solder balls to accurate positions on a surface of a printed circuit board.
2. Description of the Related Art
Recently, in accordance with miniaturization of electronic apparatuses and improvement of performance of the electronic apparatuses, semiconductor devices such as a semiconductor chip, or the like, have gradually been highly integrated, and an interval between bump patterns of the semiconductor devices has become denser as compared with the related art.
Therefore, a method of forming hemispherical or spherical bumps by a reflow process of injecting a predetermined amount of molten solder onto a substrate on which accommodating parts coinciding with patterns of the semiconductor device are formed and heating the molten solder has been suggested.
That is, after the accommodating parts such as holes or grooves coinciding with the patterns of the semiconductor chip are formed on the substrate by an etching process, when a reflow process of injecting the molten solder into the accommodating parts and heating the molten solder is performed, the molten solder becomes the hemispherical or spherical bumps due to surface tension.
Here, a process of injecting the molten solder into the accommodating parts on the substrate is performed by a molten solder injection head. The molten solder injection head serves to melt bulk solder before being molten and then inject molten solder to a position into which the molten solder is to be injected. In this configuration, the substrate is installed with a mask of which accommodated portions are opened, such that the molten solder is injected into only the accommodating parts of the substrate through the mask.
Meanwhile, in a scheme of supplying a solder ball according to the related art, patterns are formed on a substrate, a metal mask in which holes coinciding with the patterns are formed is aligned with the substrate, and the solder balls are injected through the holes of the metal mask using a squeegee on the metal mask. Then, the reflow process is performed on the substrate into which the solder balls are injected to melt the solder balls, thereby closely adhering and coupling the solder balls onto the patterns of the substrate.
However, in the scheme of supplying a solder ball according to the related art, as a fine pitch specification of the pattern progresses, since it is difficult to align the mask and the substrate with each other, it is difficult to manufacture a mask matched to fine pitch patterns and a manufacturing cost of the fine pitch patterns is increased even though the fine pitch patterns may be manufactured.
In addition, in the case in which the patterns formed on the substrate and the holes formed in the mask are not appropriately aligned with each other, the solder balls are not injected onto upper surfaces of the patterns, but are injected into erroneous positions in the vicinity of the patterns, such that a defect occurs in the substrate.